Where'd you get this file from? Sounds like a corrupt QT file.
As you see in the whitepaper link somebody posted above, there's a reference to Apple ProIO compatible firewire devices and cards. These aren't cards and devices from Apple. It is a reference to the API our developers (like BlackMagic and AJA) use when building drivers that are compatible with Final Cut Studio.
vout is the standard term for a video output device. ARGB is alpha, red, green, blue.
It's odd for a QT file to display this data so my only guess is that it's a corrupt file.
-Paul from Apple